I have seen this thread several times and want to put down my thought... though i don't think anyone will agree. First, I am hoping there is know one asking that needs real help. Like many say, it is a permanant solution to a temp problem in most cases. However, I do believe there are people in chronic pain that is beyond the understanding of others. This pain may be physical or mental. They live in agony on a level only known to them and they are in true hell. Medicine is unable to help them and they seek this to be in peace. It should be an option to them and I find others wrong in not letting them have the dignity they deserve. These people are not weak. They are often very alone and have used more strength than others can phathom to keep going. I wish them peace and comfort.
I think that we get caught up in this "It's-wrong-to-feel- ad-or-really-depressed" mentality which is so pushed on us by mainstream American culture. This only makes people who feel bad or horrible feel even worse than they already are. You don't "fix" depression (and anxiety, too); it is something that is part of your experience; it cannot get shooshed out by your simple command (no thoughts and feelings can be). You must go to all the dark places in the mind and fully experience the darkness all while learning to become a wise observer so you can see sadness and depression for what they really are: just thoughts and feelings. That is how healing begins. However, this is a long process, not a quick, one-stop fix. And, sadly, there are some people who become so enslaved to their depressive experience, whether impulsively or over period of long planning, that they end it all. That is indeed a tragedy, and we're all somewhat responsible as a society.
We need to stop judging those who admit to being depressed. Some of them live awful lives, and never can you know what it's like if you've never been in their shoes. Just be loving and compassionate, and help them acknowledge their feelings.
It is imperative to get toxic people out of your life. That has already been mentioned by earlogjam.